Braille is the language of visually impaired readers whose vision is impaired to the extent that they cannot read printed material. Reading Braille relies on the sense of touch, where reading is done by running a finger over a combination of characters.
A typical Braille character is comprised of six raised pins or bumps in a Braille cell grid having three rows high and two columns wide. Different combinations of the six pins represent different characters. In other applications, a Braille cell may be comprised of 8 or more Braille dots arranged in a grid four or more rows high and two columns wide.
Refreshable Braille Displays (“RBDs”) are devices that allow visually impaired readers to review work or read material, which an enabled reader can do on a computer screen. RBDs range in terms of the number of characters presented on one line, but most standard displays can present in the range of from 40 to 80 cell characters at a time.
Unfortunately, many visually impaired people are forced to use the traditional audio device method to review work or read material due to the scarce supply and high cost of RBDs. This problem stems from the fact that the Braille displays currently available are very expensive to produce and maintain. These devices typically utilize a dedicated actuator for each raised character dot in a cell grid. These actuators expand when an electric potential is applied to them, producing a change in the mechanism leading to a protruding bump. Due to the complexity and intricacy of the actuators and the RBDs, repairs are expensive and inconvenient because they require the user to relinquish their unit for the duration of the repair. Because moving, mechanical parts are used, these displays receive routine maintenance and require periodic repair.
Improvements in such devices producing refreshable Braille text for tactile reading by the blind and visually impaired could broaden accessibility of computer services such as electronic books, e-mail and other network access, and general computer use to the blind. Improvements in cost and reliability would facilitate more widespread use of RBDs.